Medical device

Abstract

A safety shield assembly for an intravenous apparatus is provided including a needle, a needle hub, a forward shield, a guide element, and a locking member. The needle hub is in fluid communication with a proximal end of the needle and includes a pair of flexible wings. The shield includes a distal blunting end having a distal aperture and a proximal needle passageway. The shield is moveable from a retracted position, in which the needle tip is exposed through the distal aperture, to an extended position, in which the needle tip is withdrawn from the aperture and is covered by the blunting end. The guide element is arranged on the hub for slidably accommodating the shield for movement from the retracted position to the extended position. The locking member locks the forward shield with respect to the guide element in the extended position, upon slidable movement of the shield into the extended position.

What is claimed is:  
     
         1 . A safety shield assembly for an intravenous apparatus, comprising: 
 a needle having a distal needle tip;    a needle hub in fluid communication with a proximal end of said needle and including a pair of flexible wings;    a forward shield including a distal blunting end having a distal aperture and a proximal needle passageway, wherein said shield is moveable from a retracted position in which said needle tip is exposed through the distal aperture to an extended position in which said needle tip is withdrawn from said aperture and is covered by said blunting end;    a guide element arranged on said hub for slidably accommodating said forward shield for movement from said retracted position to said extended position; and    locking means for locking said forward shield with respect to said guide element in said extended position, upon said slidable movement of said forward shield into said extended position.    
     
     
         2 . The assembly of  claim 1 , wherein said forward shield further comprises a finger contact surface.  
     
     
         3 . The assembly of  claim 2 , wherein said forward shield further comprises a barrier arm interposed between said distal blunting end and said finger contact surface.  
     
     
         4 . The assembly of  claim 3 , wherein said guide element further comprises a guide groove in slidable connection with the barrier arm.  
     
     
         5 . The assembly of  claim 4 , wherein said locking means comprises at least one inwardly directed projection on said guide groove, said projection and said shield being configured so as to allow distal movement of said shield along said guide groove and to prevent retrograde movement of said shield from said extended position.  
     
     
         6 . The assembly of  claim 5 , wherein said shield further comprises a wedge-shaped locking projection having a wider proximal end than a distal end, said locking projection being capable of exerting a lateral expanding force on said projection of said guide groove when said shield is moved distally.  
     
     
         7 . The assembly of  claim 6 , wherein said locking projection is on said barrier arm.  
     
     
         8 . The assembly of  claim 7 , wherein said distal movement of said locking projection of said barrier arm beyond said projection of said guide groove emits an audible sound.  
     
     
         9 . The assembly of  claim 6 , wherein said locking means comprises two substantially opposed inwardly directed projections.  
     
     
         10 . The assembly of  claim 9 , wherein each of said two projections includes an indent for accommodating said locking projection of said shield.  
     
     
         11 . The assembly of  claim 4 , wherein said barrier arm is arched, said guide groove defines a substantially rectilinear opening, and whereby movement of said shield along said guide groove into said extended position moves said needle tip off-center with respect to said distal aperture.  
     
     
         12 . The assembly of  claim 1 , further comprising visual detection means for determining when said shield is in said extended position.  
     
     
         13 . The assembly of  claim 12 , wherein said visual detection means includes a first color segment on said shield and a second color segment on said guide element, whereby said first and second color segments form a transverse color band when said shield is in said extended position.  
     
     
         14 . The assembly of  claim 1 , further comprising retaining means for releasably retaining said shield in said retracted position.  
     
     
         15 . The assembly of  claim 14 , wherein said retaining means comprises a retaining projection on said guide element and a corresponding ramped recess on said shield, whereby said retaining projection and recess are in releasable engagement when said shield is in said retracted position.  
     
     
         16 . The assembly of  claim 1 , further comprising a removable needle cap having a polygonal sidewall defining a cavity for receiving said needle, wherein a proximal end of said cap releasably engages a portion of said guide element when said shield is in said retracted position.  
     
     
         17 . The assembly of  claim 16 , wherein said polygonal sidewall is configured so as to be incapable of engaging said guide element when said shield is in said extended position.  
     
     
         18 . The assembly of  claim 1 , wherein said blunting end includes an access port, the assembly further comprising: 
 a spring arranged concentrically about said needle and interposed between a distal end of said needle hub and said blunting end, and    a latch including a distal arm, a proximal lever, and a pivot point therebetween, said latch being pivotally connected to said shield at said pivot point, wherein said latch is moveable between a closed position, in which said pivot arm extends through said access port to retain said spring and an opened position in which said pivot arm releases said spring onto said blunting end.    
     
     
         19 . A safety shield assembly for an intravenous apparatus, comprising: 
 a needle;    a needle hub in fluid communication with a proximal end of said needle and including a pair of flexible wings;    a forward shield including a distal blunting end, a proximal finger contact surface, an arched barrier arm interposed between said blunting end and said finger contact surface, and a wedge-shaped locking projection having a wider proximal end than a distal end, wherein said shield is moveable from a retracted position in which said needle tip is exposed through said distal aperture to an extended position in which said needle tip is withdrawn from said aperture and is covered by said blunting end; and    a guide element arranged on said hub for slidably accommodating said shield for movement from said retracted position to said extended position, said guide element including a guide groove having a pair of inwardly directed projections, whereby said inwardly directed projections engage said locking projection to prevent retrograde movement when said shield is in said extended position.    
     
     
         20 . The assembly of  claim 19 , wherein said blunting end includes an access port, said assembly further comprising: 
 a spring arranged concentrically about said needle and interposed between a distal end of said needle hub and said blunting end, and    a latch including a distal arm, a proximal lever, and a pivot point therebetween, said latch being pivotally connected to said shield at said pivot point, wherein said latch is moveable between a closed position in which said pivot arm extends through said access port to retain said spring and an opened position in which said pivot arm releases said spring onto said blunting end.